0) I'm running seti@home since 2000, as you can see
1) it's the firts time I see what I' tryng to explain now

I'he got an infinite loop of "black screen and restart".
I have seen that PC hang and restart happens some minutes after restart.
So I had some time to try something.
I have tried to stop boinc (exiting as soon as it starts)
This is working.
PC continue to work and doesn't restart any more.
So this was a strong suggestion to someting connecterd with seti (the only one project I run)
As I see boinc running, I have to wait some seconds in orded to see next hang, so my olny two neurons told me that may be it was something about GPU.
In this moment Boinc is stopped so I can write you.
later I will do some test but I prefere to wrte someting now, just to help you in helping me (and perhaps also other cruncers).

host is http://setiathome.berkeley.edu/show_host_detail.php?hostid=2693912

Or it could be just a tired power supply or graphics card getting close to failure.

Ok, I was thinking the same thing.
But later I have noticed that "black screen and restart" is appening every time I suspend work using Boinc icon in the appliction bar (suspend all or suspend GPU). As I restart, after some seconds I get the problem. Some times even if I exit from boinc and restart it. Seconds, I think, are the ones necessary to prepare the data for GPU and send data to it.
I stop GPU because when I use my PC with a VOIP application, sound is not good (I listen good but my interlocutor doesn't) and I have seen that if I stop BOINC (or olny GPU) the sond is good. As I restart the GPU task, I get the "black screen and restart". And at restart I get a new stop. I never have this in orher situations. I see that if PC is autorestartng (after maintenance) I don't have problems.
So I think that can be something in the suspend/restart in the 7.0.25 version
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